Buoyancy control apparatus for underwater swimming

ABSTRACT

A buoyancy control apparatus for underwater swimming includes a non-expandable housing having a fixed volume and having each of a predetermined shape and a predetermined size. An air chamber and a water chamber sealed from the air chamber are formed within the housing. A pump, disposed in a fluid communication with the water chamber and with a source of water, is operable for at least one of introducing such water into the water chamber and discharging such water therefrom and a controller is provided for operating the pump.

FIELD OF INVENTION

The present invention relates, in general, to underwater swimming equipment and, more particularly, this invention relates to a buoyancy control apparatus for underwater swimming.

BACKGROUND TO THE INVENTION

Buoyancy control devices have been used by scuba divers generally in the form of an inflatable jacket worn by the diver for many years. When the diver reaches a depth at which he or she wishes to remain for a time, the diver manually inflates and deflates this jacket using the compressed gas stored in the breathing tanks until a point of neutral buoyancy is found.

However, if the diver ascends or descends following setting the inflation of the jacket, the pressure of the water surrounding the diver rises or falls. Accordingly, this change in pressure causes the inflatable jacket to increase or decrease in volume and thus alters the volume of water displaced by the jacket with a consequential change in the buoyancy provided by the jacket.

By way of further explanation, when the diver descends, the rise in pressure causes the volume of the jacket to decrease. The volume of water displaced by the jacket is thus reduced causing the effect of reducing the buoyancy of the diver to a state of negative buoyancy. This further causes the diver to descend at a steadily increasing rate.

If the diver ascends, than the drop in pressure causes the volume of the jacket to increase. The volume of water displaced by the jacket is thus increased and this has the effect of raising the buoyancy of the diver to a state of positive buoyancy. This causes the diver to ascend at a steadily increasing rate.

In order to achieve neutral buoyancy again, the diver has to add or remove air to or from the jacket, by trial and error until neutral buoyancy is again achieved. This process can be repeated numerous times during a dive. The current systems require a great deal of user intervention and consumes a portion of available air supply. This reduces the amount of useful “bottom time” that the diver can spend in a dive.

Furthermore, it is important that a diver can accurately control their rate of ascent. It is well known that coming up too fast can be very dangerous. Nitrogen accumulated in a diver's body, if not given enough time to come out of the body's tissue, can form bubbles. These bubbles can cause discomfort, pain and even death—this condition is commonly referred to as the bends. Without constant user adjustment, the above described inflatable jacket device causes a steadily increasing rate of ascent, which brings with it the risk of experiencing the bends.

Efforts have been made to improve buoyancy control of the diver. U.S. Pat. No. 3,695,048 to Dimick, et al; U.S. Pat. No. 3,643,449 to Murphy; U.S. Pat. No. 4,437,843 to Birle; U.S. Pat. No. 4,779,664 to Courtney; U.S. Pat. No. 3,695,048 to Greenwood; U.S. Pat. No. 5,221,161 to Toy et al; and U.K. Patent 1 532 411 disclose various arrangements including a rigid tank and control means for varying the amount of air within such rigid tank for regulating buoyancy of the diver. However, the above prior art fails simply and economically to regulate such buoyancy and further fails to enable the diver to control rate of the descend or ascend.

Therefore, there is a need for an improved buoyancy control apparatus for underwater swimming that enables the diver to regulate desired buoyancy and control a rate of the descend or ascend.

SUMMARY OF THE INVENTION

According to one embodiment of the invention, there is provided a buoyancy control apparatus for underwater swimming. Such buoyancy control apparatus includes a non-expandable housing having a fixed volume and having each of a predetermined shape and a predetermined size. An air chamber and a water chamber sealed from the air chamber are formed within the housing. A pump, disposed in a flow communication with the water chamber and with a source of water, is operable for at least one of introducing such water into the water chamber and discharging such water therefrom. A controller is provided for operating the pump.

According to another embodiment, the present invention provides a buoyancy control apparatus for underwater swimming which includes a non-expandable housing having a fixed volume and having each of a predetermined shape and a predetermined size. An air chamber and a water chamber sealed from the air chamber are formed within the housing by one of a piston slideably and sealably disposed within the housing providing for the air chamber being axially opposed to and axially aligned with the water chamber and a flexible bag disposed within the housing and forming the water chamber. A first passageway communicates an interior of the air chamber with a source of ambient air. A second passageway communicates an interior of the water chamber with a source of water.

According to yet another embodiment of the invention, there is provided a buoyancy regulating apparatus for a buoyancy device used in underwater swimming. Such buoyancy device includes a fixed volume, non-expandable housing having an air chamber and a water chamber formed therein. The water chamber is sealed from such air chamber. The buoyancy regulating apparatus includes a housing having a predetermined shape. A water transfer means disposed within the housing and in a fluid communication with the water chamber and with a source of water and operable for at least one of introducing such water into the water chamber and discharging such water therefrom. A controller is provided for operating the water transfer means.

According to a further embodiment, the instant invention provides a novel means, engageable with a predetermined portion of an apparatus employed for underwater swimming, for equalizing of air in an air chamber of a buoyancy control device with a surrounding water.

OBJECTS OF THE INVENTION

It is, therefore, one of the primary objects of the present invention to provide a buoyancy control apparatus for underwater swimming.

Another object of the present invention is to provide a buoyancy control apparatus for underwater swimming that enables simple and economical control of desired buoyancy.

Yet, another object of the present invention is to provide a buoyancy control apparatus for underwater swimming that enables control of the descend or ascend rate.

A further object of the present invention is to provide a buoyancy control apparatus for underwater swimming which visually indicates the rate of such ascend or descend.

An additional object of the present invention is to provide a buoyancy control apparatus for underwater swimming which incorporates pressure equalization features.

In addition to the several objects and advantages of the present invention which have been described with some degree of specificity above, various other objects and advantages of the invention will become more readily apparent to those persons who are skilled in the relevant art, particularly, when such description is taken in conjunction with the attached drawing Figures and with the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective exploded view of a buoyancy control apparatus of the present invention illustrating a housing assembly according to one embodiment of the invention;

FIG. 2 is a cross sectional side view of the housing assembly taken along the lines 2-2 of FIG. 1;

FIG. 3 is a perspective view of the buoyancy control apparatus of the present invention illustrating a control unit used with the housing assembly of FIG. 1;

FIG. 4 is a perspective exploded view of the control unit of FIG. 3;

FIG. 5 is a perspective exploded view of the buoyancy control apparatus of the present invention illustrating a mouthpiece arrangement according to one embodiment of the invention for use with the housing assembly of FIG. 1;

FIG. 6 is a plan view of the mouthpiece assembly of FIG. 5;

FIG. 7 is an elevation view of the mouthpiece assembly of FIG. 5;

FIG. 8 is a cross sectional view of the mouthpiece assembly taken along the line 8-8 of FIG. 7;

FIG. 9 is a perspective exploded view of the buoyancy control apparatus of the present invention illustrating a mouthpiece arrangement according to another embodiment of the invention for use with the housing assembly of FIG. 1;

FIG. 10 is a plan view of the mouthpiece assembly of FIG. 9;

FIG. 11 is an elevation view of the mouthpiece assembly of FIG. 9;

FIG. 12 is a cross sectional view of the mouthpiece assembly taken along the line 12-12 of FIG. 11;

FIG. 13 is a perspective exploded view of a buoyancy control apparatus of the present invention illustrating a housing assembly according to another embodiment of the invention;

FIG. 14 is a cross sectional view of the housing assembly of FIG. 13; and

FIG. 15 is a schematic diagram of the buoyancy control apparatus of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Prior to proceeding to the more detailed description of the present invention, it should be noted that, for the sake of clarity and understanding, identical components which have identical functions have been identified with identical reference numerals throughout the several views illustrated in the drawing figures.

Reference is now made, to FIGS. 1-15, wherein there is shown a buoyancy control apparatus, generally designated 10, for underwater swimming.

In particular reference to FIGS. 1-2, there is shown a first essential element which is a housing assembly 11 constructed according to one embodiment of the present invention. Such housing assembly 11 includes a housing member 14 which is shown in a form of a hollow cylinder 14 preferably having a cross-section in the shape of a kidney bean. A piston 12 is slideably movable inside the cylinder 14 and is sealed against the inside walls of the cylinder 14 by way of at least one O-ring type seal 16. Preferably, a pair of seals 16 are employed within the cylinder 14. Each end of cylinder 14 is sealed with an end cap 18 and a seal 20.

In a further reference to FIG. 2, such piston 12 forms a first chamber 26 and a second chamber 28. By way of example, air is held in the first chamber 26, and water is held in the second chamber 28. It will be understood that as piston 12 moves, the volume of air in the first chamber 26 changes at the same time as the volume of water in the second chamber 28. By changing the volume of air in the first chamber 26, the buoyancy of the housing assembly 11 may he adjusted. Piston 12, cylinder 14 and ends 18 are formed from a non-expandable material, such as PVC, in a thickness rigid enough to substantially resist changes in volume of the chambers at depths normally experienced in underwater swimming. The seals 16 and 18 are made from a suitable rubber material.

One end cap 18 is provided with a first passageway 22 in communication with the first chamber 26. The other end cap 18 is provided with a second passageway 24 in communication with the second chamber 28. Each passageway 22 and 24 has a predetermined shape and a predetermined size. The presently preferred shape is round and the presently preferred size is about 1 cm in diameter.

Another essential element of the present invention is a controller, generally designated 30, and best shown in FIGS. 3 and 4. Such controller 30 has two main functions. It operates to add or remove water from the second chamber 28 of housing 11, and it provides an indication of how much water is in the second chamber 28.

The controller 30 includes a water transfer means, such as a pump 32 for at least one of adding such water into the second chamber 18 and removing such water therefrom. Accordingly, the pump 32 is connected to the second passageway 24 of the second chamber 28 via a tube 34. In the presently preferred embodiment of the invention, the pump 32 is powered by a compressed gas drawn from a scuba divers air tank 2 and operates to move the piston 12 by adding or removing water from the second chamber 28 as will now be described.

To add water to the second chamber 28 quickly, a first switch 36 is used. When actuated, preferably by a pressing action, the first switch 36 activates a first air valve 38 which allows pressurized air to flow from the diver's main tank 2 through piping 40 towards a first turbine 42. The pressurized air drives the turbine 42 in a clockwise direction, as shown in FIG. 4.

The first turbine 42 is keyed to a driveshaft 44, which in turn drives a first impeller 46, mounted for rotation within a housing 33, in a clockwise direction. A second impeller 48, also mounted within the housing 33 and engages the first impeller 46 and moves therewith causing water to flow from outside, through a filter 50, piping 52, then through piping 54 and out through the tube 34 and then to the second chamber 28, thus causing movement of the piston 12. The first turbine 42 also drives a knob 56 which is also keyed to the driveshaft 44.

Similarly, to remove water from second chamber 28 quickly, a second switch 37 is used. When this is pressed, it activates a second valve 39 which allows pressurized air to flow from the diver's main tank 2 through piping 41 towards a second turbine 43 which is also keyed to the driveshaft 44. The pressurized air drives the second turbine 43 in a counter-clockwise direction, as shown in FIG. 4, which drives the first impeller 46 in the counter-clockwise direction. This causes water to be drawn from the second chamber 28 via the tube 34, piping 54, piping 52, and out through filter 50 to the outside and thus causes movement of piston 12. The second turbine 43 also drives knob 56 in an anti-clockwise direction.

To add or remove water from the second chamber 28 slowly, impeller 46 can be turned in either a clockwise or counter-clockwise direction by way of manually turning knob 56. This provides for finer control of the buoyancy of the housing assembly 11.

Piping 40 and 41 are connected to a y-split connection (not shown) which is then connected to the main air tank 2. Each turbine 42 and 43 is provided with shrouds 58 and 59, respectively, to assist with driving of the turbines by compressed air. The components of the controller are housed between a front case 62 and a rear case 64.

Whichever method is used to add or remove water from the second chamber 28, the knob 56 moves in a clockwise or counter-clockwise direction. Furthermore, it does so relative to motion of both turbines 42 and 43 and impellers 46 and 48. This relativity is preferably on a 1 to 1 basis, with knob 56 rotating once for every revolution of turbines 42 and 43 and impellers 46 and 48. Alternatively, gears (not shown) could be employed to provide for alternative relativities.

The rotation of the knob 56 can be quantified by use of a scale 60. Scale 60 is provided with a plurality of graduated scale markings 61, spaced from each other at a predetermined angle, and can be set in any desired position. Scale 60 does not rotate along with knob 56. This allows the user to judge just how much of a revolution knob 56 makes relative to the scale 60. Since the motion of the knob 56 reflects inward or outward flow of water to the second chamber 28, being able to quantify movement of the knob 56 allows a relative quantification of the amount of water moving in or out of the second chamber 28 and thus an indication of how much water is in the second chamber 28 at any given time.

Furthermore, a display 57, such as a counter, is coupled to the knob 56, by way of meshing gears 63 and 65, to record clockwise or anticlockwise rotations as a positive or negative number value respectively. This provides another way in which the rotation of the knob 56 can be quantified. Again, this quantification has a relevance to the amount of water in the second chamber 28. A simple button 80 maybe provided to reset the counter 57 in order to establish a starting point of reference.

Referring now to FIGS. 5-8, the pressure equalization feature will now be described. This feature allows for balancing the pressure of air in the first chamber 26 with the surrounding water pressure. A standard mouthpiece 66 is connected to a standard regulator 68 by way of a connector 70. Connector 70 is provided with an aperture 72. In use, a tube 73 connects the first passageway 22 of the housing assembly 11 to the aperture 72 of the connector 70.

At any depth, air at the pressure of the surrounding sea water is provided to the diver's mouth by a second stage of the regulator 68. By connecting the first chamber 26 to the connector 70, the pressure of air in the first chamber 26 is maintained equal to the air provided by the regulator 68. If the diver descends, then the pressure of air provided by the regulator 68 will increase and air will flow into the first chamber 26. Similarly, if the diver ascends, then the pressure of air provided by the regulator 68 will decrease and air will flow out of the first chamber 26.

As a further mechanism for allowing air to escape from the first chamber 26, a one-way release valve 76, either manually or pressure operated, may be provided on the tube 73, or may be connected directly to the first chamber 26. This release valve 76 may be provided as a precaution if the regulator 68 is not able to expel escaping air from the first chamber 26 quickly enough. All tubing mentioned needs to be wide enough to allow smooth flow of air in and out of the first chamber 26.

Referring to FIGS. 9-12, therein illustrated is a mouthpiece 166 according to another embodiment of the invention. Such mouthpiece 166 is provided with aperture 172 and fits directly onto the standard regulator 68.

By use of the above described device, the diver can set their desired level of buoyancy at any depth in the water by using controller 30 as described above. The buoyancy of the housing assembly 11 is regulated by adjusting the position of the piston 12 by pumping water into, or out of, the second chamber 28. This in turn alters the volume of air held in the first chamber 26. If the diver then moves to a different depth, the volume of air in the first chamber 26 remains constant.

The pressure of the air may change, but the changes in the mass of the air in the first chamber 26 due to changes in pressure are negligible. So, the buoyancy of the device remains substantially unchanged despite the diver ascending or descending during their dive. This obviates the need for the diver to adjust buoyancy in order to allow for changes in depth.

Referring to FIGS. 13 and 14, there is illustrated a housing assembly, generally designated 210, according to another embodiment of the invention. Such housing assembly 210 includes a hollow housing 214, an expandable means 212, such as a flexible bag or bellows, end caps 218, and end seals 220. The flexible bag 212 is made from a flexible waterproof and airtight material such as polyethylene, PVC, silicone rubber or the like.

Air may enter and leave a first chamber 226 via a first passageway 222. Water may enter and leave a second chamber 228 via a second passageway 224. The second chamber 228 is the space inside flexible bag 212. In this embodiment, the piston has been replaced by the flexible bag 212. The volume of air in the first chamber 226 is regulated by adjusting the volume of water inside the flexible bag 212. In all other respects, operation of the device is the same as for the embodiment described above. The controller 30 shown in FIGS. 3 and 4 may be used to adjust the volume of water in the second chamber 228.

The bellows 212 could increase or decrease in internal volume by expansion or contraction and could be formed from dip coated vinyl, rubber coated polyester fabric or urethane coated polyester fabric and various combinations thereof.

The chamber defined by the internal space of flexible bag or bellows 212 could contain air instead of water, and the space outside the flexible bag or bellows 212 could contain water instead of air.

Although the present invention has been shown in terms of the piston 12 being actuated by a pump 32, it will be apparent to those skilled in the art, that the present invention may be applied to other forms of actuators such as mechanical or electrical actuators. For instance, piston 12 could be mounted on a screw thread which can actuate the piston by rotation. The screw thread could be rotated manually by turning a handle.

Furthermore, the pump 32 operated by compressed air from the diver's air tank 2 may be replaced with another type of pump, such as an electric pump.

Additionally, references to “air” in this specification includes air that might be encountered in scuba diving conditions including air in a diver's air tank 2, and air that is inhaled or exhaled by a diver.

Thus, the present invention has been described in such full, clear, concise and exact terms as to enable any person skilled in the art to which it pertains to make and use the same. It will be understood that variations, modifications, equivalents and substitutions for components of the specifically described embodiments of the invention may be made by those skilled in the art without departing from the spirit and scope of the invention as set forth in the appended claims. 

1. A buoyancy control apparatus for underwater swimming, said buoyancy control apparatus comprising: (a) a non-expandable housing having a fixed volume and having each of a predetermined shape and a predetermined size; (b) means disposed within said housing for forming an air chamber and a water chamber sealed from said air chamber; (c) a water transfer means in fluid communication with said water chamber and with a source of water, said water transfer means operable for at least one of introducing such water into said water chamber and discharging such water therefrom; and (d) a control means for operating said water transfer means.
 2. The apparatus, according to claim 1, wherein said apparatus further includes a pressure equalizing means arranged to substantially equalize a pressure of air in said air chamber with a surrounding water pressure.
 3. The apparatus, according to claim 2, wherein said pressure equalizing means includes a passageway communicating an interior of said air chamber with a source of ambient air.
 4. The apparatus, according to claim 3, wherein said passageway has a connection with one of a mouthpiece and a connector disposed intermediate to such mouthpiece and a pressure regulator valve connected to a source of compressed air.
 5. The apparatus, according to claim 3, wherein said pressure equalizing means includes a release valve operably disposed within said passageway and connected for releasing an air pressure formed in said air chamber when said air pressure exceeds such surrounding water pressure.
 6. The apparatus, according to claim 1, wherein said water transfer means is a pump in fluid communication with said water chamber and with such source of water.
 7. The apparatus, according to claim 6, wherein said pump includes: (a) a housing; (b) a first impeller rotatably mounted within said housing; (c) a second impeller rotatably mounted within said housing and engageable with said first impeller; (d) a first passageway formed in said housing in fluid communication with such source of water; and (e) a second passageway formed in said housing in fluid communication with a passageway formed in said water chamber.
 8. The apparatus, according to claim 7, wherein said control means includes: (a) a driveshaft coupled to said first impeller; (b) a first turbine attached to said driveshaft for rotation therewith; (c) a second turbine attached to said driveshaft for rotation therewith and spaced from said first turbine; (d) a first valve connected to a source of compressed air and operable to deliver such compressed air to said first turbine for rotating said first turbine, said drive shaft and said first impeller in a first direction; (e) a second valve connected to such source of compressed air and operable to deliver such compressed air to said second turbine for rotating said second turbine, said drive shaft and said first impeller in a second direction, said second direction is opposite to said first direction; (f) a first switch for operating said first valve; and (g) a second switch for operating said second valve.
 9. The apparatus, according to claim 8, wherein said apparatus further includes a housing containing said water transfer means and said control means and means engageable with said housing for indicating a volume of water disposed in said water chamber.
 10. The apparatus, according to claim 9, wherein said indicating means includes a scale attached to said housing and a knob connected to said drive shaft for rotation therewith in said first and said second direction.
 11. The apparatus, according to claim 10, wherein said indicating means further includes a display being in geared connection with said knob for displaying a quantity of full revolutions of said knob.
 12. The apparatus, according to claim 10, wherein said scale is one of rigidly attached to said housing and rotatably attached to said housing independently from a rotation of said knob.
 13. The apparatus, according to claim 1, wherein said means for forming said air chamber and said water chamber includes a piston mounted for sliding movement within said housing and at least one seal engageable with an outer surface of said piston and engageable with an inner wall surface of said housing for sealing said air chamber from said water chamber, wherein said air chamber being axially opposed to and axially aligned with said water chamber.
 14. The apparatus, according to claim 1, wherein said means for forming said air chamber and said water chamber includes one of a flexible bag and bellows.
 15. A buoyancy control apparatus for underwater swimming, said buoyancy control apparatus comprising: (a) a non-expandable housing having a fixed volume and having each of a predetermined shape and a predetermined size; (b) means disposed within said housing for forming an air chamber and a water chamber sealed from said air chamber, said means being one of a piston mounted for sliding movement within said housing and at least one seal engageable with an outer surface of said piston and engageable with an inner wall surface of said housing for sealing said air chamber from said water chamber, wherein said air chamber is axially opposed to and axially aligned with said water chamber and a flexible bag disposed within said housing and forming said water chamber; (c) a first passageway for communicating an interior of said air chamber with a source of compressed air; and (d) a second passageway for communicating an interior of said water chamber with a source of water.
 16. A buoyancy regulating apparatus for a buoyancy device used in underwater swimming, such buoyancy device including a fixed volume, non-expandable housing having an air chamber and a water chamber formed therein, such water chamber is sealed from such air chamber, said buoyancy regulating apparatus comprising: (a) a housing having a predetermined shape; (b) a water transfer means disposed within said housing and in fluid communication with said water chamber and with a source of water, said water transfer means operable for at least one of introducing such water into said water chamber and discharging such water therefrom; and (c) a control means for operating said water transfer means.
 17. In an apparatus employed for underwater swimming, the combination comprising a means engageable with a predetermined portion of such apparatus for equalizing pressure of air in an air chamber of a buoyancy control device with a surrounding water pressure.
 18. The combination of claim 17, wherein said pressure equalizing means is one of a passageway formed in a mouthpiece and a connector disposed intermediate to such mouthpiece and a pressure regulator valve connected to a source of compressed air, said connector having said passageway formed therein. 